> > > You'd need a sine wave source of fairly accurate frequency, and a
> > > way to control the amp gain to set output voltage, and keep it
> > > constant under load changes.
> >
> >         Very few inverters, at least the kind you'd find in a
> hardware store,
> >generate sine waves, the usually generate some sort of "step
> wave" that has
> >the same RMS as a "normal" sine wave, and that "kind of" looks
> like a sine
> >when feeding "typical" loads.
>
> True, and this is the only reason I can think of for using the audio amp
> approach.

        Frankly I can't see the reasoning behind that approach either, regulation
will be a BIG problem, nevermind heat. Personally, if you NEEDED a sine wave
I'd go with a switch mode converter design using PWM to get a "perfect" sine
wave (after a simple filter), if you REALLY need a SUPER clean sine wave
then I would go the amp (linear) route, but I've never encountered a need
for such a "perfect" supply. TTYL

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